* next attempt to fix yield day for multiple inverters #1016
* fix export settings date #1040
* fix time on WebUI (timezone was not observed) #913#1016
* fix Contrast for Nokia Display #1041
* attempt to fix#1016 by improving inverter status
* added option to adjust effiency for yield (day/total) #1028
- rework display type handling: remove uneeded checks because defined context from which functions are called
- default initialize "mMono" pointer (potential illegal memory access)
- define EXACTLY one display type for ePaper display (type 10). There is no need to use ranges and distinguish oled from epaper display. Simply one switch/case
- correct type handling for display type (javascript). Event handler gives a string instead of number (display type)
* attempt to fix MqTT `YieldDay` in `TotalValues` #927
* attempt to fix MqTT `YieldDay` and `YieldTotal` even if inverters are not completly available #929
* fix wrong message 'NRF not connected' if it is disabled #1007
* fix display of hidden SSID checkbox
* changed yield correction data type to `double`, now decimal places are supported
* corrected name of 0.91" display in settings
* attempt to fix MqTT zero values only if setting is there #980, #957
* made AP password configurable #951
* added option to start without time-sync, eg. for AP-only-mode #951
* fix HMS-800 and HMS-1000 assignments #981
* make nrf enabled all the time for ESP8266
* fix menu item `active` highlight for 'API' and 'Doku'
* fix MqTT totals issue #927, #980
* reduce maximum number of inverters to 4 for ESP8266, increase to 16 for ESP32